Re: Pioneer DVR-106D issues
> >Jörg, I don't care about silly arguments about who's right, but I have
>
> Well, I don't like to be the one who is right but of course,
> it makes no sense if I write something that _may be right_ and someone
> else telle all people this is nonsense.
It was not formulated as "this is nonsense," but as "this is hardly
relevant." Note that the latter does *not* mean "irrelevant" or
"nonsense." It means "it *might* be irrelevant."
> >to agree 100% with Andy's assessment of the situation. He gave sound
> >reason for his conclusion. I am still very interested in your detailed
> >technical explanation on why a fast CPU with 0% load only manages a 0.4x
> >DVD burn speed because of a lack of enabled DMA.
>
> Let me comment this by telling you that I definitely did see exactly this
> behavior on a system that cannot properly do DMA.
Once again, readcd exhibiting maximum performance does prove that DMA is
on, but not vice versa. readcd exhibiting lower than expected
performance means "something is not right," it's doesn't actually tells
you that DMA is off. It makes DMA a most like culprit, but it doesn't
make it the only one.
OK, requestor has reported that readcd performs at >2-3x accompanied by
irresonsiveness of the system. This *does* appear as lack of DMA and it
agrees pretty well with those reports from NEC users I mentioned
yesterday. Yes, DMA must be off (or not being used on that particular
data flowpath), *but* I don't think it's the factor resposible for
further <1/5x performance loss, from >2x to 0.4x that is. In other words
lack of DMA is the *least* problem and search for limiting factor may
*not* stop there. A.
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